Jacob Harth¹ (), Cameron Wysocky¹, Lauren Hacker², Billy Hammond¹, Lisa Renzi-Hammond¹; ¹University of Georgia, ²Emerging Vision Explorations (EVE) Research

Introduction: Age-related cataracts are a leading cause of vision problems in the U.S., and the primary treatment is surgery. Cataracts gradually impair vision, which can make everyday activities more difficult and dangerous, increasing the risk of accidents and limiting personal independence. While cataract surgery is often considered when individuals report difficulties in daily tasks, these reports usually do not account for the challenges people face in specific environments, such as bright sunlight or when driving at night with headlights. This study aimed to better understand how people with cataracts experience visual discomfort in real-world conditions and when cataract surgery might be needed. Methods: Data were aggregated from clinical trials conducted at the University of Georgia between 2017-2022. Participants (N=232; 18-78 years; M=42.39±14.65 years, 76% Female, 33% non-White) were divided into 4 groups: those without cataract (n=102), with early cataract (n=67), with advanced cataract (n=40), and those who recently had cataract surgery (n=23). Participants had otherwise good ocular health, as determined by an eye care provider. Glare discomfort was measured objectively by bioimaging the squint response and subjectively by participant rating of discomfort. Results: Participants with advanced cataracts had a significantly stronger squint response (M=8.16mm±4.75mm) than those without cataracts (M=4.10mm ±2.34mm, t=-6.79, p<.001), with early cataracts (M=4.55mm±2.60mm, t=-5.07, p<.001), and post-surgery (M=2.13mm±1.81mm, t=- 5.83, p<.001). Measures of subjective and objective glare discomfort were significantly correlated when controlling for age (r(209)=.34, p<.001) and iris lightness (r(209)=.33, p<.001). Conclusions: People with more severe squint responses to light may benefit most from cataract surgery, as it may reduce their heightened discomfort from glare (e.g., sunlight or headlights). This research expands our practical understanding of when cataract surgery may be necessary to improve a person’s quality of life.